James Mulvaney is an adjunct professor in the law and police science department at John Jay College of the City University of New York.

A “good shoot” in police lingo is one in which officers use deadly force to prevent a suspect from inflicting serious harm. A “bad shoot” is one in which there might have been a nonlethal alternative. The Oct. 3 shooting near the Capitol, which we now know to be a sad case involving a mentally ill woman and a toddler who has lost her mother, was the latter.

It was an emotionally charged situation. Less than three weeks after 12 people were killed in the Navy Yard shooting and just three days into a tense federal government shutdown, Washington was already on edge when the Secret Service and Capitol Police were confronted by a driver who appeared to attempt to breach security barriers at the White House and then the Capitol and who at least twice refused their orders to stop . The car chase through the city streets would have further skyrocketed the officers’ blood pressure and adrenaline. They were responsible for protecting the tourists and other alarmed bystanders they sped past, as well as multiple branches of government. There was no time to thoroughly assess the situation. They had to make snap decisions based on instinct and training.

Officers fired 17 shots over several minutes before one round killed the driver, 34-year-old Miriam Carey, on the northeast side of the Capitol.

Of course, the officers couldn’t have known that Carey had been diagnosed with postpartum depression with psychosis and that her understanding of their commands may have been clouded by an alternate reality in her head. But if they’d had better training, they might have realized that she wasn’t intentionally defying their orders as much as she was panicked, confused and in the midst of an emotional breakdown. They might have figured out a way to calm her down without killing her.

Standard training regimes prepare officers to deal with people demonstrating various degrees of defiance. Police are taught to apply a “force continuum” that starts at its lowest level with the presence of an officer on the scene and escalates, as needed, through verbal commands; a light touch; grabbing, pushing or tackling; nonlethal weapons; and eventually deadly force.

But that model doesn’t address how, as they ratchet up force, police officers can distinguish people who are defiant because of bad intent from people who don’t understand or aren’t able to process their commands.

The most common cause of unintentional defiance is a language barrier. Depending on where they patrol, officers may learn how to say “stop” and “drop the gun” in Spanish, Haitian Creole, Somali or Hmong. But there are still cases in which language difficulties and snap judgments lead to deadly outcomes. The 1999 shooting of Amadou Diallo in New York may have been one of them. Diallo, an immigrant from Guinea with somewhat limited English, didn’t comply with plainclothed officers when they ordered him to “show us your hands” — a complicated phrase for a nonnative speaker. Police killed him as he stood unarmed in the vestibule of his apartment building.

In other cases, failure to comply may be explained by cognitive impairments. In January, 26-year-old Robert Ethan Saylor resisted security officers who tried to escort him out of a Frederick movie theater and told him that he couldn’t stay for a second showing of “Zero Dark Thirty” without a ticket. Saylor’s physical traits should have identified him to the officers as someone with Down syndrome, and his aide said she explained Saylor’s condition to them, but the officers didn’t seem to realize that applying the force continuum wasn’t appropriate. In the ensuing altercation, Saylor was choked to death. Maryland Gov. Martin O’Malley has since pledged to improve training for first responders on how to interact with people with developmental disabilities.

I’ve conducted that sort of training for police and first responders on Long Island, focusing especially on autism. I recommend that officers look for clues ranging from an Autism Society bumper sticker to behavior that sometimes accompanies severe autism — such as spinning, hand flapping or speech with repetitive phrases — and I warn them not to confuse that behavior with intentional defiance or assault. When my son Dan was about 11 years old, he wandered away from a soccer field and, through a convoluted set of events, ended up in police custody. Officers thought he was exercising his Miranda rights as he sat in silence. They didn’t realize that he’s autistic and can’t speak.

Mental illness often doesn’t come with many visible clues. There was no bumper sticker on Carey’s black Infiniti to alert the Secret Service and Capitol Police to what was happening. But the officers should have been trained to look for signs of confusion: One witness told The Washington Post, “It looked like [the driver was] scared or lost.” And if the officers had noticed the child in the back seat, they might have deduced that the woman refusing to comply with their orders at gunpoint and driving erratically through the streets was operating with impaired judgment.

Before escalating force, officers should try to determine if their commands are getting through. If suspects aren’t responding as a reasonable person might expect them to, officers should try a different approach. Use short, simple sentences. Try a request instead of an order. Shouting like an Army drill sergeant can be counterproductive, driving an upset subject to violence. Sometimes soothing words work better. Think of Antoinette Tuff, who in August persuaded a gunman at a Georgia elementary school not to shoot by telling him that he wasn’t alone in his troubles.

Had the officers outside the Capitol taken a breath rather than taking aim, they might have recognized that Carey, who was unarmed, was more of a threat to her toddler and herself than to the White House or Congress. The right move would have been to contain her car and wait for her to surrender.